Hi i have RX 580 with elpida memory.
I get very large screen at startup and black screen in windows.
I have tried flashing org bios.
Memory resistance 32 ohm.

What do you mean by "large"?

I think it's 640*480 resolution.
menzy
What video out are you used? Try another video out, may be all video out.

Yes its 640*480 i tired hdmi not working DP not working only on dvi i get large screen at startup and black screen in windows.

Make a thorough review of the video outputs, apparently DVI damaged pin's. Check the power supply on the video outputs (5 volts DVI and HDMI and 3.3 volts DP) then check the clock and date for all video outputs.
write the exact model and manufacturer of the video card, so it will be easier to help you.

Thank you will check now model is GV-RX580GAMING-4GD.
Pins on dvi and hdmi looks okei